I just got back from an extended trip to London and had good luck with a Three pay as you go SIM plan. £15 got you 3000 texts, 300 mins, and unlimited data. I used an iPhone 5 and although the data was 3G and not LTE, I was pleased by both the speed and the coverage. I had no issues anywhere in London or on side trips 30mins to an hour away.
I’m based in the US and use Sprint. You need to insure that your handsets are unlocked for international use (which Sprint will do for free). The steps are a little complicated, but do-able.
One benefit: Three allowed wi-fi tethering which costs extra with Sprint. Another benefit of unlimited data.
Thumbs up from me to Three! less than a minute ago
giffgaff offers 500 MB of data for 5 pounds, which ramps up to 10 pounds if you also want 250 voice minutes and 1 GB.
Finally I got a 3 (http://three.co.uk) SIM for 1 pound and unlimited traffic data for 15 pounds.
You can get a 10 pounds – 500Mb plan too.
All of these things as a prepaid plan and working in less than a minute.
You get a ticket with a code to set your SIM card credit and that’s all. Take a look at their plans here.
After having a quick look, I think that
Orange: http://shop.orange.co.uk/mobile-phones/plans/planDetailPage.jsp?item=prod640006
and O2 (Text & Web tariff): http://www.o2.co.uk/tariffs/payandgo
offer the best deal. Make sure you double check before you buy/top-up though, because these things tend to change really quickly.
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